如何用 python 打印 excel 列非 null 值？

Question

I have the following excel sheet:

and want to print column 1 value if the column 2 value is not null. The output should be [1,3].

This the script created by me, but it doesn't work:

import xlrd
import pandas as pd

filename='test.xlsx'
dataframe = pd.read_excel(filename)
frame = dataframe.loc[dataframe["col2"] !=" "]
df =  frame.iloc[:, 0]

ndarray = df.to_numpy()
print(ndarray)

Answer 1

You can first filter down to nona rows and then show the values of the column you want to show:

dataframe[df['col2'].notna()]['col1'].values

Answer 2

If you print the dataframe, you will see that the empty cells are NaN :

      Col1 Col2
 0     1    a
 1     2  NaN
 2     3    b
 3     4  NaN

So, you need to use the notna() method to filter

Here is your fixed code:

import xlrd
import pandas as pd

filename='test.xlsx'
dataframe = pd.read_excel(filename)
frame = dataframe.loc[dataframe["col2"].notna()]
df =  frame.iloc[:, 0]

ndarray = df.to_numpy()
print(ndarray)